Fire boats battle a fire at the offshore oil rig Deepwater Horizon April 21, 2010, in the Gulf of Mexico off the coast of Louisiana. Multiple Coast Guard helicopters, planes and cutters responded to rescue the Deepwater Horizon 126-person crew after an explosion and fire caused the crew to evacuate.

Oil sits on the surface of the water that leaked from the Deepwater Horizon wellhead in the Gulf of Mexico April 28, 2010, near New Orleans.

A controlled burn of oil is conducted near the source of the BP Plc Deepwater Horizon oil spill in the Gulf of Mexico off the coast of Louisiana July 15, 2010. BP Plc said a pressure test on its damaged Macondo well halted the flow of oil into the Gulf for the first time in three months.

A shrimp boat passes through a heavy oil slick as it uses the deployed oil boom and absorption pads to collect the oil from the spill May 5, 2010, in Breton and Chandeleur Sounds off the coast of Louisiana. Oil leaked out of the Deepwater Horizon wellhead at a estimated rate of 1,000-5,000 barrels a day.

Oil burns during a controlled fire May 6, 2010, in the Gulf of Mexico. The U.S. Coast Guard oversaw oil burns after the sinking, and subsequent oil leak, from the sinking of the Deepwater Horizon oil platform off the coast of Louisiana.

A brown pelican, covered with oil from the BP Deepwater Horizon oil spill, sits next to a clean pelican on the rocks at Empire Jetty in the Gulf of Mexico, near Venice, La., June 15, 2010, as a team of biologists from the U.S. Fish and Wildlife Service looks to capture those covered with oil. Birds were caught and then cleaned at the Fort Jackson Oiled Wildlife Rehabilitation Center.

Greenpeace marine biologist Paul Horsman examines oil washed onto a beach with the tide at the mouth of the Mississippi River May 17, 2010, near Venice, La. BP announced that it had successfully siphoned off 1,000 barrels of oil per day from the Deepwater Horizon oil rig that exploded and sank to the bottom of the Gulf of Mexico April 22, killing 11 crew members.

Crews conduced overflights of controlled burns in the Gulf of Mexico May 19, 2010. BP Plc took steps toward attempting to cap its leaking well in the Gulf of Mexico the day before as it increased the amount of crude it's capturing and thick oil began to appear in Louisiana's wetlands.

Oil-covered brown pelicans found off the Louisiana coast and affected by the BP Deepwater Horizon oil spill in the Gulf of Mexico wait in a holding pen for cleaning at the Fort Jackson Oiled Wildlife Rehabilitation Center in Buras, La., June 9, 2010.

Workers clear off some of the oil washing on to Fourchon Beach from the Deepwater Horizon oil spill in the Gulf of Mexico July 3, 2010, in Port Fourchon, La. Millions of gallons of oil spilled into the Gulf after the April 20, 2010, explosion on the drilling platform.

A makeshift sign warned of a closed beach because of approaching oil slicks in an area affected by the Deepwater Horizon disaster and the British Petroleum oil spill off the Gulf Coast, June 11, 2010, in Grand Isle, La.

Oil floated in the Gulf of Mexico near Orange Beach, Ala., June 18, 2010. The BP Plc oil spill, which began when the leased Transocean Deepwater Horizon oil rig exploded April 20, 2010, gushed as many as 60,000 barrels of oil a day into the Gulf of Mexico, the government said.

A man walked on the beach as oil-tainted water washes ashore from the Deepwater Horizon oil spill in the Gulf of Mexico June 26, 2010, in Orange Beach, Ala. Millions of gallons of oil spilled into the Gulf after the April 20, 2010, explosion on the drilling platform.

Volunteers moved an oil-covered brown pelican found off the Louisiana coast that was affected by the BP Deepwater Horizon oil spill to a holding pen while it awaits cleaning at the Fort Jackson Oiled Wildlife Rehabilitation Center in Buras, La., June 9, 2010.

Vessels worked at the site of the Deepwater Horizon accident Aug. 10, 2010, off the shore of Louisiana. BP issued a statement saying efforts to complete the relief well would cease temporarily because of a U.S. National Weather Service prediction that there was a 60 percent chance of a tropical cyclone forming in the Gulf in 24 hours.

Oil deposited along dead marshland near Bay Jimmy Jan. 7, 2011, in Port Sulphur, La. Plaquemines Parish President Billy Nungesser said oil was still sometimes found in different parts of Plaquemines Parish. Eleven people were killed when BP's Deepwater Horizon Oil rig exploded in the Gulf of Mexico April 20, 2010.

An aerial photo taken April 16, 2012, shows the coast of Pensacola Beach, Fla., during a media helicopter flight by the BP Gulf Coast Restoration Organization. One project by the organization's Florida Trustees involves dune restoration along Pensacola Beach. The plan calls for about 394,000 native plants to be planted along a 4.2-mile stretch of beach dunes at a cost of about $586,000.